Fig. 1

Evaluation of the height of the anterior/posterior osteophyte and expansion of anterior/posterior subchondral bone depression (attrition) on the medial second quarter of the MTP using sagittal MRI. A Osteophyte height is classified into three categories (N: none, L: low, H: high) relative to a line t. B Expansion of the depression is classified into three categories (N: none, M: moderate, S: severe) based on location. ap: anterior most prominent aspect of the MTP, pp: posterior most prominent aspect of the MTP, t: a line tangent to the ap and pp